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Customer interviews: a clear guide with practical examples
A practical 2027 guide to customer interviews: a clear guide with practical examples 2027 with current definitions, decisions, checks, and review steps.
People do not usually lie in customer interviews. They answer the question you asked. The trouble is that most questions founders ask have a polite answer built into them, and the polite answer is free to give.
So treat the question as the instrument. A bent instrument gives you a clean-looking reading of nothing.
What an interview can actually measure
An interview is good at recovering the past and bad at predicting the future. That single limit decides almost everything about how you should run one.
You can get a reliable account of what someone did last Tuesday, what it cost them, what they tried first, what they gave up on, and who else was involved. You cannot get a reliable account of what they will buy in March. Not because they are being evasive, but because they genuinely do not know, and answering feels like being helpful rather than being asked to predict.
Three things people report badly about themselves:
- Future behaviour. "Would you use this?" measures how much the person likes you.
- Frequency. People round toward the memorable. Ask for a count, or ask them to open the calendar.
- Reasons. People give you the reason they can articulate, which is often not the reason they acted. Get the sequence of events instead and draw your own conclusion.
The leading question, and four ways it leaks
A leading question hands over the answer and asks for a signature. It usually leaks in one of these ways.
It names the problem for them. "Do you find scheduling frustrating?" now contains the word frustrating, and agreeing is cheaper than disagreeing. Ask what happened the last time they scheduled something instead.
It describes your solution first. Once someone knows what you built, everything they say afterwards is a response to your idea rather than a description of their life. Keep the product out of the conversation until you have the story you came for.
It asks for a rating on a scale you invented. "How big a problem is this, one to ten?" produces a number with no unit. Ask what they spent on it instead: hours, money, arguments, workarounds.
It offers a hypothetical. "If there were a tool that did this, would you try it?" Every honest person says yes. Yes costs nothing.
Here is the shape of the repair. The right-hand column is not a script. It is the move: replace an opinion request with a request for a specific past event.
| Instead of asking | Ask |
|---|---|
| Would you pay for something like this? | What did you spend money on the last time this came up? |
| Do you have a problem with X? | Walk me through the last time you did X, from the beginning. |
| How often does this happen? | How many times did it happen last month? Can we look? |
| What features would you want? | What did you do when the tool you had could not do it? |
| Would this save you time? | How long did it take you last time, start to finish? |
| Who makes this decision? | Who signed off the last thing you bought like this? |
Running the conversation
Ask for one story, not a survey. "Tell me about the last time" is the workhorse. One concrete episode, followed all the way through, is worth more than twenty general impressions. When they generalise, pull them back: "Was that the case in the last one too?"
Let the silence run. Most people give you the tidy answer first, stop, and then keep talking if you do not fill the gap. The second thing they say is usually less rehearsed. Counting to four before you speak is an unglamorous technique that works.
Follow the friction, not the feature. When someone mentions a workaround, stop and stay there. A spreadsheet somebody maintains by hand, a message they send twice, a step they do outside the official system. Workarounds are the fossil record of an unsolved problem, and they cost the person something real, which is why they are trustworthy.
Ask what they already tried. Someone who has tried three things and abandoned all three is telling you the problem is worth effort. Someone who has never looked is telling you it is not, whatever they say next.
Notice who is not in the room. The person describing the problem and the person who can authorise a fix are often different people. Ask early who else would be involved, and what happened the last time that person was asked for money.
Do not defend anything. The moment you explain why they misunderstood, the interview is over and a sales call has started. Write the objection down and thank them.
Compliments are a warning sign
Enthusiasm in an interview costs the speaker nothing. It is the cheapest thing a person can give you and it feels like the most valuable, which is a bad combination.
The way to test enthusiasm is to make it slightly expensive while you are still on the call. Ask for something small and real: an introduction to a colleague, a copy of the spreadsheet they described, half an hour next week to look at it together, permission to email them when there is something to try. Not a payment. Just a cost.
The person who says the idea is brilliant and will not spend fifteen minutes on it has told you something. The person who is lukewarm but pulls up their calendar has told you something else. Believe the calendar.
Who counts as a valid interview
Two filters, applied before you book anything.
Do they have the problem, recently, without being prompted? If you have to explain the problem before they recognise it, they are not in your sample yet. They might be later. Right now they will only tell you about your explanation.
Can you find more people like them, in a way you could repeat? If your only route to this person was that you already knew them, the interview still teaches you about the problem, but it teaches you nothing about whether the audience is reachable. Keep those two questions separate in your notes.
Friends and former colleagues are not useless. They are just biased in a known direction, and they are a channel you cannot scale. Use them to sharpen your questions. Do not use them to decide.
Reading what you collected
Write up each conversation within a day, while you still remember what the pauses meant. Separate three things in your notes and never let them merge:
- What the person said happened.
- What you observed (they could not find the file; they had two systems open; they laughed at the price).
- What you concluded.
The third one is yours. It is the part that will be wrong. Keeping it in its own column is what lets you go back later and re-read the evidence when your conclusion changes.
Then look for the same detail appearing in different lives. One person's workaround is an anecdote. The same workaround, invented separately by four people who do not know each other, is a design specification. Patterns across independent sources are the only kind of pattern worth acting on, and they show up faster than you expect once the questions stop leading.
What would change your mind
Before a batch of interviews, write down the sentence you are hoping to hear and the sentence that would make you stop. If there is no sentence anyone could say that would disappoint you, you are not running a test. You are collecting quotes.
This is also the honest way to decide when to stop interviewing. Not a target number. Stop when new conversations stop surprising you, and when the next real question can only be answered by asking someone for money or for time rather than for an opinion. At that point interviews have given you what they can, and the work moves on to offer testing and a price someone has to refuse.
What interviews cannot settle
They cannot tell you whether people will pay. Only a price and a refusal can do that.
They cannot tell you the size of the market. Interviews are depth, not breadth, and it takes very few good conversations to convince yourself of something that is true for six people and false for six thousand. Market validation is a separate job with separate evidence.
They cannot tell you whether you can build or deliver it. That question belongs to you, and no customer can answer it.
And they cannot tell you whether you asked the wrong people. Nothing inside the room can tell you that. It is the one error that survives every good interview technique, so it is worth checking who you have talked to before you trust what they said.